Internal-combustion engine



June l 1926.

H. MICHEL INTERNAL COMBUSTION ENGINE Filed 001:. 26, 1922 PatentedJune 1, 1926.

UNITED STATES PATENT OFFICE.

HERMANN -MICHEL, OF VOORDE I. HOLSTEIN, GfIELRCMIAN'Y.

INTERNAL-COMBUSTION Application tiled-October 26, 19,22, Serial No. 596,976, and in Germany October 28, 1921.

My invention relates toimprovements 1n internal combustion engines, and more particularly to engines of the constant pressure or Diesel type in which the air is heated by compression to a temperature higher than the ignition ltemperature of the fuel, for the purpose of raising the thermodynamic efficiency. As is known to those skilled in the art-in Diesel engines the increase of the total eiiciency has practicallynot been as high as should be theoretically expected, because inA en ines of this type the pressure of the explo 'ng charge is high and causes a considerable increase of the loss of energy by friction in the crank mechanism. Thereby -the gain. in power caused by the increase of thethermo-dynamic efficiency Vwas largely offset by the loss caused by a reduction of the mechanical efficiency.

This objectionable feature of the Diesel engine was particularly conspicuous in case of very high compression, for which reason it has been found necessary to run the engines at lower pressure than was originally intended. Practically, engines of the Diesel type have ordinarily been run with a compression of from to 38 atmospheres, while originally higher pressureswere Aaimed at.

The object of the improvements is to provide an engine in which the loss of energy caused by the friction in the crank mecha- -nism is reduced, and with this object in view my invention consists in 'providing in lieu of the crank mechanism cam mechanism'cooperating with'two or more pistons or plungers for controlling. the .movement thereof and y transmitting the power therefrom.

, I am aware that it has heretofore been'proposed to provide power transmittingmechanism of this type in internal combustion en- 4 gines of the explosion type but such constructions have not been commercially sucu cesful, forthe reason that the compression pressureA is comparatively low and only the working stroke is performed at high pressure, so that the total loss of energy by friction is so small that. there has never been a necessity for reducing the friction by providing-a, cam way in connection with pistons operating in opposite directions.

In order that my invention be more clearly understood an exam le embodying the same has been shown in t e accompanying drawing, in which the same reference characters have been used in' all the views to indicate corresponding parts. In said drawing,-

Fig. l, is a longitudinal section of the engme,

Fig. 2, is a cross-section taken on the line 2-2 of Fig. l, and A Fig. 3, is an indicator or pressure diagram.

,The drawings illustrate an internal combustion engine. of the two cycle Diesel type comprising a stationary pylinder a having two pistons b reciprocating therein in opposite directions, which pistons cooperate with cam ways c controlling the movement thereof and provided on rotary disks or'iiy wheels d which are connected with each other rigidly as by an'annular member s. The fluid pressure acting on the pistons is transmitted to the cam ways c through the intermediary of rollers e mounted on anti-friction `bearings g disposed in cross-heads fconnected with the pistons b and guided by sliding engagement with the cylinder a. To insure the proper movement of the pistons corresponding to the cam ways c when starting the engine subsidiary rollers m of the cross-heads f bear on cam ways o provided on the fly wheels ai. In

a bearing i a driven shaft h is mounted which is directly connected with the rotary disks or fly wheels al. Liquid fuel is supplied to the combustion chamber k common to both pistons through a port Z. The engine shown' in the drawing is a two-stroke cycle combustion engine. Scavenging air is supplied through ports p controlled by the lower pis- 4 ton b, and the exhaust gas is discharged through ports r controlled bythe upper piston b. It will be noted that the rollers e (and m) are carried by` crossheads f or equivalent parts guided separately from the pis- Atons b, this being necessary to enable the parts to receive without lateral binding the heavy tangential strains occurring in the opera- Y tion of Diesel engines.A

In the diagram shown in Fig. 3the line w indicates the pressure-of the charge, and the line 2 the forces caused by the moving masses of an internal combustion engineof the In my improved engine the loss by friction is materially reduced, because there is no reaction in the bearing of the driven shaft, and the loss of energy caused by friction 1s reduced in my system in which the power is transmitted through rollers running on cam ways, as compared to power transmission by means of crank mechanism. It is true the force exerted by the pistons b on the cam members or Ways c has a radial component, but since the two pistons always son of the high pressure of combustion the dimensions of the parts of the power transmitting mechanism are large, which results in a large leverage of the forces caused by friction and a high cost of the manufacture of the engines.

In view of the aforesaid conditions in my improved engine the pressure of the combustion stroke can be raised, so that the advantages of the Diesel system can be availed of to a higher degree.

Another important feature of my improved engine resides in the fact that ,the breaking of the crank shaft is avoided, which in high speed engines of the Diesel type of the ordinary construction is frequently Caused by oscillations transmitted to the crank shaft froln heavy members of the power transmitting gearing. In my improved engine ythe shaft is connected with the Sy wheel or wheels rotating at uniform spee The reduction of the friction results in a reduced consumption of lubricants. Thereby the-cost of the operation is reduced. By reason of the reduced dimensions of the elements of the power transmitting gearing the total mareas weight of the engine is reduced, and the plant requires less room.

I claim:

l. An engine of the two cycle Diesel type, provided with a easing, a plurality of pistons arranged to reciprocate in said casing in opposite directions, separately guided reciproeating eross-heads or equivalent sliding members connected rigidly with said pistons, a cam member cooperating with said sliding members to control the position of the pistons and a rotary member supporting said cam member and including two rotatable disks connected together by vinterposed removable sectional segments whereby to enclose the operating members and to permit ready access thereto.

2. An internal combustion engine of the two cycle Diesel type comprising a central stationary casing provided with a plurality' of cylinders having a common combustion chamber, a reciprocable piston in each cylinder, spaced guides secured to said casing and extending radially outwardly from the ends of the cylinders, crossheads adapted to slidably engage said guides, a piston rod ri 'dly connecting the respective crossh'eads an pistons, an antifriction bearing in each cross head, a shaft journaled in said bearing, rollers carried by said shaft lon opposite sides of said crosshead,a rotary member, guides having cam ways for the rollers on each side of the crossheads, said guides being rigidly 'attached to the rotary member.

3. In an internal combustion engine, a stationary casing formed to provide a single cylinder open at both ends and a central combustion chamber, a pair of pistons adapted for 'simultaneous reciprocation in opposite directions within said cylinder, piston rods rigidly connected to said pistons and extending beyond the ends of the cylinders, crossheads secured to said piston rods, guides for the crossheads carried by the casing, pairs of rollers journaled in the crosshcadsl and positioned on each side thereof, a rotary member having means forming a pair of inwardly and outwardly facing cam guides, the respective rollers in each pair engaging one of said cam guides.

HERMANN MICHEL. [L s] 

